The present invention relates to a cartridge alignment mechanism, and more particularly to a cartridge alignment mechanism for use in business machines such as inkjet printers.
In inkjet printing, a cartridge contains ink, and a printhead is mounted on one end of the cartridge, connected with the reservoir. The cartridge is detachably mounted on a carriage, adapted to move bidirectionally above a media sheet. When the cartridge is mounted on the carriage, it is necessary to maintain lock-in and alignment.
Single-sided alignment is generally applied in cartridge alignment. In this case, a biasing force is provided against the cartridge, forcing the cartridge to lock and remain in a single side thereof. For example, U.S. Pat. No. 4,907,018 discloses a printhead cartridge and carriage assembly in which a force loading spring pad abuts a portion of the cartridge. U.S. Pat. No. 5,392,063 discloses a unitary latch assembly, in which each latch end is provided with a cam of a low friction material in the form of a horizontal section of an inclined cylinder to abut four cartridges.
Since the biasing force is not symmetrical, however, the cartridges disclosed in U.S. Pat. Nos. 5,392,063 and 4,907,018 may tilt in alignment. In U.S. Pat. No. 5,392,063, the cam is of a low friction material to reduce biasing due to friction. It is impossible, however, to completely eliminate friction between the cam and the cartridge.
Further, in U.S. Pat. No. 4,907,018, a leaf spring is applied to abut the sidewall of the cartridge. Accordingly, the sidewall is deformed. In this case, U.S. Pat. No. 5,504,513 discloses a compensated structure of the side wall for the cartridge to reduce deformation thereof. Nonetheless, deformation is not totally eliminated.